Drill cutter



1933- E. A. REED 1,921,701

DRILL CUTIER Filed Aug. 15 1928 42 INVENTOR.

EA. [feed BY M 11%,

ATTORNEYS I I application Serial No. 194,315, filed May 26, 1927.}

Patented Aug. 1933 UNITED srAIrss P TE- DRILL CUTTER I I I I Eat! A. Reed, Tulsa, Okla. I j 7 Application Atmns, 192s. Serial No. 299,855

11c1aims. j (o1.j255- 71' r This invention relates to improvements in earth boring drills, and constitutes an improvement upon the structure shown in "my copending The present invention relates more'particularly to the frusto-conical type of cutter and the manner of mounting the same upon aIbit head.

It is-anobject of my'invention-to provide a mounting for frusto-conical cutters which will aflford a -maximum' bearing "surface area and which at the same time will facilitate the re moval and substitution of both the cutter and bearing elements.

.- Further objects relate tothe construction and 'design' of the parts with a view 'to simplifying and, effecting economies in the I manufacture and'use thereof, as will more definitely appear from the following description and accompanym a n s Referring ,now to the several views of the drawing, I i

'Fig. l is a view partly bit head having a pair of frusto-oonical roller cutters mounted thereon in accordance with the present invention, I I I I Fig.2 is a top plan view of the cutter, I I

. fig. 3 is a top plan view of the fru'sto-conical bushing, and

' Fig. 4 is a jMy'present invention is shown in connection view of the bushing in side'jeleva 'with'a'." one piece drill head construction indi{ cated generally by the reference character 1.

This drill'head is formedwitha pair of spaced,

depending spindles or legs 2 on which the" re spective rotarycutters are mountedi The space 3 :between the two spindles'is just sufiicient to accommodate the two rotary cuttersin substan ti allyabutting relation. The drill head isprovidedat its upper end with the usual threaded operation. The lower' horizontal surface of the spindle is formed I with a substantially rec tan'gular recess 12", the purpose of which will-'.

the spindle 2.

I nular groove 11 of the cutter. in vertical section of threads as indicated at 17 whichthreads coactbe hereinafter pointed", out; it bushing i is formed with an internal frusto co'nical surface of such size as to snugly fit'the-frusto-conical sur-,

face of the spindle. This bushing, also has a similarly formed external bearing surface with. which the international frus to-conical surface of the roller cutter has bearing I engagement 'I'he internal surface of --the cutter-isformed as shown in Figure 2 'with' an annular groove or channeljll and the' external s urfaceof-the' tangular lug for engagement 'With'said channel.

The internal surface of the bushing 'isalso provided with a'substantially rectangular'lug l? for engagement in the aforesaid recess .12" in is rotatably mounted on the bushing by vn-tue oflug '12 of the bushing engaging in the fan:

' In orderto lock the parts in the assembled I relation thus described, lfprovide' a locking pin 13 seated within a transverse bore 116 -in-the I spindle and adapted to be projected through an:

aperture 14 in bushing '7 and into engagement I with the-annular recesss 11,0f the cutter; The- I outer end of the pin 13 is providediwith screw 1 with corresponding threads in the outer end I of bore 16 for the purpose of securing the pin in place. It will readilyfbe appreciated that with pin '13 in operative position ,asshown, the cutter, bushing and spindle elements will be securelylocked in assembledrelation and that by merely withdrawing the pin 'in a late'r-al idi-x. rectiony these-elements may be Y sembled. R E 1 'An important characteristioof'thefpresent'invention is the rightangular relationofthelsurface elements of the ifrusto -conicalspindle.

This is clearly representedin' Fig. -1 -wherein an axial section through thespindledisclos'es truly I vertical'and horizontal surfaces. One 'advantage ofithis construction, which is common-to this application and the application hereinabove re ferred to, is that the spindle supports the loads imposed upon it in operationsubstantiallyentirely along vertical lines, thus subjecting the spindle only to compression stresses" and sub-"- stantially eliminating all leverage-stresses; This construction possesses anjimport'ant added ad-J vantage in connection with the present invention in that it permits, the usejof a bushingof unitary construction. It should be apparent 10 bushing isf'provided with a substantially] rec-" Thus, it will be seen that the bushing isinterlocked with the spindle by means ofthe luglz and recess 12" and that thejcutter' I adily Jana-s Y that it would be practically impossible to as-' it is possible to use a bushing of unitary con-j struction andto' receive the advantages of such construction. l

The construction as thus described is of particular utility in connection with drill heads and cutters of relatively small sizes since it affords a maximum bearing surface area and yet retains all of the advantages of mountings adapted more particularly for larger drills, such for example as that shown in my copending application above referred to. ent invention may be utilized in connection with cutters and drill heads of any desired size.

It is to be understood that the present invention is susceptible of somemodification and is not necessarily limited to the precise detailsof construction herein shown and described. Therefore, it is my intentionthat the scope of my invention be unrestricted other than by the appended claims.

I claim:

1. In a device of the character described, the combination with a drill head having a substantially frusto-conical cutter supporting spindle, of a bearing member having substantially frusto-conical external and internal bearing surfaces, the latter surface being adapted to engage the frusto conical surface of said spindle, a roller cutter having an internal frusto-conical surface adapted for engagement with the ex ternal surface of said .bearing member, and means carried by said bearing member and engaging said spindle and cutter, said means serving to lock said bearing and spindle against relative rotation while permitting relative rotation of. said bearing and cutter and means carried by said spindle and engaging said cutter and bearing and serving in conjunction with the aforesaidmeans to lock said cutter, bearing and. spindle in assembled relation.

2. In, adevice of the character described, the combination with a drill head having a substantially frusto-conical cutter supporting spindle, of a bearing having substantially frusto conical external and internal bearing surfaces,

nular channel formed in the internal surfacethereof a projection on the external surface of said bearing adapted to engage in said-channel whereby said cutter is permitted torotate with respect to said bearing, interlocking means on said bearing and spindle whereby rotation of said bearing with respect to said spindle is prevented and means carried by said spindle and engaging said cutter and bearing and serving in conjunction with the aforesaid projection and interlocking means to prevent axial .separation of saidspindle, bearingand cutter.

3.In a drill, the combination with a drill face of said bushing entering the said annular 'nel.

However, the preshead having' a depending cutter supporting spindle formed with a substantially frusto-conical cutter supporting surface, of a bushing hav ing substantially frusto-conical external and formed with a continuous annular .channel, a

projection on the internal surface of said bushingentering a recess in the surface of said spindle, a second projection onthe exterior surchannel and means for locking the said parts in assembled relation, said means comprising a removable locking-plug carried by said spindle and adapted to pass through an aperture in said bushing and enter the said annular chan- 4. In a drill, the combination with a bit head having a depending leg, of a frusto-conical roller cutter provided with a continuous. interior groove, a bushing interposed between the bit f head and the roller cutter, a projection from the interior of said bushing entering a recess in thedeperiding leg of the bit head,a projection from theexterior of said bushing entering the continuous groove in the interior of the roller cutter, and means for locking theroller'lgfi cutter rotatably to the bit head, comprising a removable locking plug carried by the bit head and adapted to pass through an aperture in said bushing and enter the continuous groove formed as a concentric ring in the roller cutter. 1:19

5. In a cutter assembly, a spindle having a frusto-conica1 surface formed with a recess, a bearing formed with an inner frusto-conical surface and non-rotatably mounted on the spindle, said bearing having a projecting lug '5 extending into said recess, a cutter mounted on the bearing and being formed with an inner an- 'a frusto-conical surface which is formedwith a recess, a bearing having aninner frusto-conie cal surface and an outer frusto-conical surface and being non-rotatably mounted on the spin,- dle, a cutter having a frusto-conical inner sur-' face and being formed with an annular groove in said'surface, projections being formed' mi -T39 said bearing and extending respectively 'into' the recess and the groove, andmeans coacting with the spindle, bearing, and cutter, to maintain them free from relative axial movement, said means comprising an element extending through 3.5 said bearing and into engagement with said cutter. I

7. As an article of manufacture, abearing member having an internal frusto-conical"sur-. face formed with a projecting lug integral there- 14.9 With'and extending inwardly from said inner surface, the bearing member having an aperture formed'through the frusto-conical surface, said aperture being spaced from the apex of said conical surfaces. 1

8. As an article of manufacture, a bearing, member having internal and external frustoconical surfaces tapering in the same direction, and being formed with projecting'lugs integral therewith and extending from each of said 15G frusto-conical surfaces, the bearingmember having an aperture formed through the frusto-conical surface, said aperture being spaced' from the apexes of said frusto-conical surfaces.

,9. In a cutter assembly, a spindle formed 'with a frusto-conical surfaceat its lower end,

the lowermost element of whichis disposed'in substantially a horizontal plane, and theinnermost element in substantially a vertical plane, a bearing member formed with an inner frusto conical surface coinciding with the frusto-con ical surface of the spindle, said bearing member having an element formed integral therewith and cooperating with the spindle to pre-,

. 10;I'he combination described in claim 9' in which all portions of the spindle are positioned in a direction axially of the drill head with re-" spect to the base area of the spindle so as to transmit 1 the thrusts encountered duringthe drilling operation in a vertical direction only,

whereby to eliminate leverage 1 stresses.

11. As an article of manufacture, a bearing member having an internal frusto-conical surface, opposed elements of which arerightangularly disposed, said member having a pro j ecting lug integral therewith, and extending posed elements of which are right angularly disposed, and having a projection integralv there- EARL AiREEDlinwardly from said surface, said member also 1 having an external frusto-conical surface, op-'.

with extending outwardly, from said external I surface. r 

